This invention relates, in part, to newly identified polynucleotides and polypeptides; variants and derivatives of the polynucleotides and polypeptides; processes for making the polynucleotides and the polypeptides, and their variants and derivatives; agonists and antagonists of the polypeptides; and uses of the polynucleotides, polypeptides, variants, derivatives, agonists and antagonists. In particular, in these and in other regards, the invention relates to polynucleotides and polypeptides of human chemokine alpha-2, hereinafter referred to as xe2x80x9cCKxcex1-2xe2x80x9d.
The ability to control the migration and xe2x80x9ctraffickingxe2x80x9d of various cell types is controlled by a subset of factors, or proteins, among which chemokines are an example.
Chemokines, also referred to as intercrine cytokines, are a subfamily of structurally and functionally related chemotactic cytokines. These molecules are 8-10 kd in size. In general, chemokines exhibit 20% to 75% homology at the amino acid level and are characterized by four conserved cysteine residues that form two disulfide bonds. Based on the arrangement of the first two cysteine residues, chemokines have been classified into two subfamilies, alpha and beta. In the alpha subfamily, the first two cysteines are separated by one amino acid and hence are referred to as the xe2x80x9cCxe2x80x94Xxe2x80x94Cxe2x80x9d subfamily. In the beta subfamily, the two cysteines are in an adjacent position and are, therefore, referred to as the xe2x80x9cCxe2x80x94Cxe2x80x9d subfamily. Thus far, at least eight different members of this family have been identified in humans.
The intercrine cytokines exhibit a wide variety of functions. A hallmark feature is their ability to elicit chemotactic migration of distinct cell types, including monocytes, neutrophils, T lymphocytes, basophils and fibroblasts. Many chemokines have proinflammatory activity and are involved in multiple steps during an inflammatory reaction. These activities include stimulation of histamine release, lysosomal enzyme and leukotriene release, increased adherence of target immune cells to endothelial cells, enhanced binding of complement proteins, induced expression of granulocyte adhesion molecules and complement receptors, and respiratory burst. In addition to their involvement in inflammation, certain chemokines have been shown to exhibit other activities. For example, macrophage inflammatory protein 1 (MIP-1) is able to suppress hematopoietic stem cell proliferation, platelet factor-4 (PF-4) is a potent inhibitor of endothelial cell growth, interleukin-3 (IL-8) promotes proliferation of keratinocytes, and GRO is an autocrine growth factor for melanoma cells.
In light of the diverse biological activities, it is not surprising that chemokines have been implicated in a number of physiological and disease conditions, including lymphocyte trafficking, wound healing, hematopoietic regulation and immunological disorders such as allergy, asthma and arthritis.
Members of the xe2x80x9cCxe2x80x94Cxe2x80x9d branch exert their effects on the following cells: eosinophils which destroy parasites to lessen parasitic infection and cause chronic inflammation in the airways of the respiratory system; macrophages which suppress tumor formation in vertebrates; and basophils which release histamine which plays a role in allergic inflammation. However, members of one branch may exert an effect on cells which are normally responsive to the other branch of chemokines and, therefore, no precise role can be attached to the members of the branches.
While members of the Cxe2x80x94C branch act predominantly on mononuclear cells and members of the Cxe2x80x94Xxe2x80x94C branch act predominantly on neutrophils a distinct chemoattractant property cannot be assigned to a chemokine based on this guideline. Some chemokines from one family show characteristics of the other.
The polypeptide of the present invention has the conserved cysteine residues of the xe2x80x9cCxe2x80x94Xxe2x80x94Cxe2x80x9d region, and have amino acid sequence homology to known chemokines.
Clearly, there is a need for factors that regulate the migration of distinct cell types and their roles in dysfunction and disease. There is a need, therefore, for identification and characterization of such factors that regulate the migration of cells, particularly cells of the immune system, and which can play a role in preventing, ameliorating or correcting dysfinctions or diseases.
Toward these ends, and others, it is an object of the present invention to provide polypeptides, inter alia, that have been identified as novel CKxcex1-2 by homology between the amino acid sequence set out in both FIG. 1 (SEQ ID NO:2) and FIG. 2 (SEQ ID NO:3) and known amino acid sequences of other proteins such as Chinese hamster GRO protein set out in FIGS. 3 and 4 (SEQ ID NO:4).
It is a further object of the invention, moreover, to provide polynucleotides that encode CKxcex1-2, particularly polynucleotides that encode the polypeptides herein designated CKxcex1-2.
In a particularly preferred embodiment of this aspect of the invention the polynucleotide comprise the regions encoding the human CKxcex1-2 polypeptides in the sequences set out in FIGS. 1 and 2 (SEQ ID NO:1).
In accordance with this aspect of the present invention there is provided an isolated nucleic acid molecule encoding mature polypeptides expressed by the human cDNA contained in ATCC Deposit No. 97400 deposited on Jan. 2, 1996.
In accordance with this aspect of the invention there are provided isolated nucleic acid molecules encoding human CKxcex1-2 polypeptides, including mRNAs, cDNAs, genomic DNAs and, in further embodiments of this aspect of the invention, biologically, diagnostically, clinically or therapeutically useful variants, analogs or derivatives thereof, or fragments thereof, including fragments of the variants, analogs and derivatives.
Among the particularly preferred embodiments of this aspect of the invention are naturally occurring allelic variants of human CKxcex1-2.
It also is an object of the invention to provide CKxcex1-2 polypeptides, particularly human CKxcex1-2 polypeptides, that may be employed for therapeutic purposes, for example, to treat and/or prevent tumors, chronic infections, leukemia, T-cell mediated auto-immune diseases, parasitic infections, psoriasis, asthma, allergy, to regulate hematopoiesis, to stimulate growth factor activity, to inhibit angiogenesis and to promote wound healing.
In accordance with this aspect of the invention there are provided novel polypeptides of human origin referred to herein as CKxcex1-2 as well as biologically, diagnostically or therapeutically useful fragments, variants and derivatives thereof, variants and derivatives of the fragments, and analogs of the foregoing.
Among the particularly preferred embodiments of this aspect of the invention are variants of human CKxcex1-2 encoded by naturally occurring alleles of the human CKxcex1-2 gene.
It is another object of the invention to provide a process for producing the aforementioned polypeptides, polypeptide fragments, variants and derivatives, fragments of the variants and derivatives, and analogs of the foregoing. In a preferred embodiment of this aspect ofthe invention there are provided methods for producing the aforementioned CKxcex1-2 polypeptides comprising culturing host cells having expressibly incorporated therein an exogenously-derived human CKxcex1-2-encoding polynucleotide under conditions for expression of a human CKxcex1-2 polypeptide in the host and then recovering the expressed polypeptide.
In accordance with another object the invention there are provided products, compositions, processes and methods that utilize the aforementioned polypeptides and polynucleotides for research, biological, clinical and therapeutic purposes, inter alia.
In accordance with certain preferred embodiments of this aspect of the invention, there are provided products, compositions and methods, inter alia, for, among other things: assessing CKxcex1-2 expression in cells by determining CKxcex1-2 polypeptides or CKxcex1-2-encoding mRNA; assaying genetic variation and aberrations, such as defects, in CKxcex1-2 genes; and administering a CKxcex1-2 polypeptide or polynucleotide to an organism to augment CKxcex1-2 finction or remediate CKxcex1-2 dysfunction.
In accordance with certain preferred embodiments of this and other aspects ofthe invention there are provided probes that hybridize to human CKxcex1-2 sequences.
In certain additional preferred embodiments ofthis aspect ofthe invention there are provided antibodies against CKxcex1-2 polypeptides. In certain particularly preferred embodiments in this regard, the antibodies are highly selective for human CKxcex1-2.
In accordance with another aspect of the present invention, there are provided CKxcex1-2 agonists. Among preferred agonists are molecules that mimic CKxcex1-2, that bind to CKxcex1-2-binding molecules or receptor molecules, and that elicit or augment CKxcex1-2-induced responses. Also among preferred agonists are molecules that interact with CKxcex1-2 or CKxcex1-2 polypeptides, or with other modulators of CKxcex1-2 activities, and thereby potentiate or augment an effect of CKxcex1-2 or more than one effect of CKxcex1-2.
In accordance with yet another aspect of the present invention, there are provided CKxcex1-2 antagonists. Among preferred antagonists are those which mimic CKxcex1-2 so as to bind to CKxcex1-2 receptors or binding molecules but not elicit a CKxcex1-2-induced response or more than one CKxcex1-2-induced response. Also among preferred antagonists are molecules that bind to or interact with CKxcex1-2 so as to inhibit an effect of CKxcex1-2 or more than one effect of CKxcex1-2 or which prevent expression of CKxcex1-2, for the treatment of disease and dysfinction mediated by CKxcex1-2.
In a further aspect of the invention there are provided compositions comprising a CKxcex1-2 polynucleotide or a CKxcex1-2 polypeptide for administration to cells in vitro, to cells ex vivo and to cells in vivo, or to a multicellular organism. In certain particularly preferred embodiments of this aspect of the invention, the compositions comprise a CKxcex1-2 polynucleotide for expression of a CKxcex1-2 polypeptide in a host organism for treatment of disease. Particularly preferred in this regard is expression in a human patient for treatment of a dysfunction associated with aberrant endogenous activity of CKxcex1-2.
Other objects, features, advantages and aspects of the present invention will become apparent to those of skill from the following description. It should be understood, however, that the following description and the specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only. Various changes and modifications within the spirit and scope of the disclosed invention will become readily apparent to those skilled in the art from reading the following description and from reading the other parts of the present disclosure.